1. Field of the Invention
This invention relates to an elevator that is raised and lowered along guide rails provided on a hoistway of a multi-storey building. In particular, it relates to an elevator passenger car in which the feel of the ride in the elevator is improved.
This invention further relates to a device for evaluating the feel of the ride in an elevator.
2. Description of the Related Art
FIG. 14 shows the-construction of a prior art elevator passenger car of this type. Specifically, guide rails 2 are each erected vertically on both side walls of a hoistway 1 of a multistorey building, and a passenger car 4 is provided that is free to be raised and lowered between these two guide rails 2, by means of a main rope 3.
This passenger car 4 is constructed of a car frame 5 and a cage 6 mounted therein and equipped with a door, door opening/closing mechanism, illumination device, and in-cage operating panel etc. not shown, Furthermore, above and below car frame 5 there are mounted a total of four guide devices 7. These guide devices 7 are each provided with guide rollers 7a that are in rolling contact with the two side faces and end face of one of two guide rails 2. Displacement of guide roller 7a is adjusted by means of an elastic body 7b.
Further, respective floor-support frames 8 are provided extending below car frame 5. Respective anti-vibration rubber elements 9 are arranged in four locations so as to support cage 6, between these floor supporting frames 8 and the bottom face of cage 6.
Additionally, a load sensing unit 10 that measures the load carried by passenger car 4 is arranged between floor support frames 8 and cage 6.
However, during ascent and descent, due to bending of guide rails 2, bending produced by installation errors etc in installing guide rails 2, and steps etc at joints of guide rails 2, vibration is transmitted from guide rails 2 to passenger car 4. This vibration is transmitted to the passengers in passenger car 4, making the elevator ride less comfortable.
Conventionally therefore it was sought to improve the feel of the elevator ride by absorbing the vibration by anti-vibration rubber elements 9 and/or elastic body 7b.
However, with the construction described above, it is not possible to completely remove the vibration from guide rails 2. Furthermore, depending on the running speed, it can happen that the frequency of applied vibration (1.4 Hz to 2.7 Hz) due to forcible displacement such as bending of guide rails 2 may coincide with the first order natural frequency (1.5 Hz to 4 Hz) of elevator passenger car 4, resulting in resonance, which produces very large transverse swaying of passenger car 4. This greatly lowers the comfort of the ride in passenger car 4.
Furthermore, even if the first order natural frequency of passenger car 4 is set in the design stage so as not to coincide with applied vibration frequencies from guide rail 2, it is possible for the first order natural frequency of passenger car 4 to change with change in the-loading of passenger car 4, resulting in resonance occurring.
For example, the first order natural frequency of a passenger car of an elevator in which the weight of the passenger car itself is 2500 kg and which is to carry 1600 kg changes, depending on changes (0-1600 kg) in the passenger live load, in the range 1.9 Hz to 3.1 Hz.
Next, the method of evaluating the feel of the ride in an elevator will be described. A conventional method of measuring vibration for evaluation of the feel of the ride in an elevator, and a device therefor, will be described with reference to FIG. 15.
In FIG. 15, passenger car 4 is constituted by car frame 5 and cage 6 carried thereon.
The method of measuring the vibration for evaluating the feel of the ride in passenger car 4 was first of all to detect the vibration in each direction of the floor surface of cage 6 by means of an accelerometer 24 mounted on the floor of cage 6, these measurements being converted to voltage. These voltage signals were then amplified using an amplifier 25, and the vibration was measured by inputting these vibration waveform data into a data recorder 26.
In this way, the feel of the ride in passenger car 4 was evaluated by measuring the vibration acceleration of the floor surface of cage 6 of passenger car 4.
However, with the above construction, the vibration of the floor surface of passenger car 4 is measured, so the feeling actually experienced by a person cannot be determined. It is therefore difficult to evaluate the actual feel of the elevator ride.
Furthermore, in evaluating the feel of the ride, the evaluation of the feel of the ride must be made by analysis or data processing using the vibration data of the passenger car floor surface, so the person making the evaluation needs to have experience, knowledge and technical skill and furthermore some time is required to perform the evaluation. It is therefore difficult to evaluate the feel of the elevator ride immediately on site.